It is intended to carry out clinical studies on patients with acute cerebrovascular disease as well as biochemical and ultrastructural studies of tissue exposed to conditions in vitro related to acute anoxic and hypoxic episodes. The clinical studies will include patients receiving treatment in an intensive care fashion and a number of parameters will be monitored using computer techniques. These include blood pressure, cardiac output, EKG arrhythmia analysis, blood oxygen content, evoked potentials and arterial Ph PCO2, PO2 sodium and potassium. Treatment will be instituted in these patients depending upon the computerized findings. Biochemical studies of mammalian cortex respiring in vitro will be made under conditions of anoxia, acidosis, and alkalosis, hypercapnia, variation in ionic concentration and variation in temperature. Carbohydrate, amino acid energy and lipid metabolism will be studied and ultrastructural studies will be carried out. The relation of hypertensive state to patients with cerebral infarcts will be studied by measuring levels of catecholamines derived from the circulation as well as from nerve fibers innervating the blood vessels.